Find Communities by: Category | Product

I think we do not need to go back much in time to recall some of recent incidents at the sea when it comes to oil spills. One of the recent most mentioned is 2010 Gulf spill at BP platform. Oil spills can be controlled by chemical dispersion, combustion, mechanical containment, and/or adsorption. Spills may take weeks, months or even years to clean up. Environmental effects are devastating.



Oil penetrates into the structure of the plumage of birds and the fur of mammals, reducing its insulating ability, and making them more vulnerable to temperature fluctuations and much less buoyant in the water. Oil can impair a bird's ability to fly, preventing it from foraging or escaping from predators. As they preen, birds may ingest the oil coating their feathers, irritating the digestive tract, altering liver function, and causing kidney damage. Together with their diminished foraging capacity, this can rapidly result in dehydration and metabolic imbalance. Some birds exposed to petroleum also experience changes in their hormonal balance, including changes in their luteinizing protein. The majority of birds affected by oil spills die without human intervention. Some studies have suggested that less than one percent of oil-soaked birds survive, even after cleaning, although the survival rate can also exceed ninety percent, as in the case of the Treasure oil spill. Heavily furred marine mammals exposed to oil spills are affected in similar ways. Oil coats the fur of sea otters and seals, reducing its insulating effect, and leading to fluctuations in body temperature and hypothermia. Oil can also blind an animal, leaving it defenseless. The ingestion of oil causes dehydration and impairs the digestive process. Animals can be poisoned, and may die from oil entering the lungs or liver. You just wish you can become Steven Seagall and kick some ***. Of course, humans are affected too. The Deepwater Horizon oil spill in the Gulf of Mexico in April 2010, for example, will have a large economic impact on the U.S. Gulf fisheries. A new study published in the Canadian Journal of Fisheries and Aquatic Sciences says that over 7 years this oil spill could have a $US8.7 billion impact on the economy of the Gulf of Mexico. This includes losses in revenue, profit, and wages, and close to 22 000 jobs could be lost. Obviosuly we depend on oil so is there a way to fight this problem once it happens?


Apparently, there is. A new type of sponge that loves oil as much as it hates water could make a big difference when cleaning up an oil spill. Researchers at Rice University and Penn State University say the tiny sponge they've developed can absorb 100 times its weight in oil. The sponge is made out of carbon nanotubes (of course). Extra boron atoms are added at all its junctions to boost the sponge's ability to absorb. One of the main reasons it works so well is because adding a bit of boron to carbon while creating nanotubes turns them into solid, spongy, reusable blocks. This helps the sponge increase its ability to absorb oil spilled in water. Watch a video about the sponge below.





The researchers believe the sponge could someday play a significant role in cleaning up oil spills.



Credits: Nature magazine, Wikipedia

Hrvoje Crvelin

Tarantula nebula II

Posted by Hrvoje Crvelin Apr 18, 2012

Remember Tarantula nebula? That wonderful image, I just learned, has been released in its full size and you may wish to download it.  I use it as background already.  However, I had to resize it. You will most certainly had to do the same.  Why?  Because it comes as 267MB file and picture has resolution of 20323x16259 pixels!!!! I can say for sure that this image can be used as desktop background for many many generation of big screens to come. You have been warned. If you wish to proceed - click here (one again, it is ENORMOUS!!!!).

Hrvoje Crvelin


Posted by Hrvoje Crvelin Apr 18, 2012

NASA's Spitzer Space Telescope was launched on August 25, 2003 from Florida's Cape Canaveral Air Force Base. Drifting in a unique Earth-trailing orbit around the Sun, Spitzer sees an optically invisible universe dominated by dust and stars. This is because it observes the universe around us at infrared scale. It can image nebulae of cold dust, peer inside obscured dust clouds where new stars are forming, and detect faint emissions from very distant galaxies. The planned mission period was to be 2.5 years with a pre-launch expectation that the mission could extend to five or slightly more years until the onboard liquid helium supply was exhausted. This occurred on 15 May 2009. Without liquid helium to cool the telescope to the very cold temperatures needed to operate, most instruments are no longer usable. However, the two shortest wavelength modules of the IRAC camera are still operable with the same sensitivity as before the cryogen was exhausted, and will continue to be used in the so called Spitzer Warm Mission.




Spitzer carries three instruments on-board:

  • IRAC (Infrared Array Camera), an infrared camera which operates simultaneously on four wavelengths (3.6 µm, 4.5 µm, 5.8 µm and 8 µm). Each module uses a 256 × 256 pixel detector - the short wavelength pair use indium antimonide technology, the long wavelength pair use arsenic-doped silicon impurity band conduction technology. The two shorter wavelength bands (3.6 µm & 4.5 µm) for this instrument remain productive after LHe depletion in the spring of 2009, at the telescope equilibrium temperature of around 30 K, so IRAC continues to operate as the "Spitzer Warm Mission".
  • IRS (Infrared Spectrograph), an infrared spectrometer with four sub-modules which operate at the wavelengths 5.3-14 µm (low resolution), 10-19.5 µm (high resolution), 14-40 µm (low resolution), and 19-37 µm (high resolution). Each module uses a 128x128 pixel detector - the short wavelength pair use arsenic-doped silicon blocked impurity band technology, the long wavelength pair use antimony-doped silicon blocked impurity band technology.
  • MIPS (Multiband Imaging Photometer for Spitzer), three detector arrays in the far infrared (128 × 128 pixels at 24 µm, 32 × 32 pixels at 70 µm, 2 × 20 pixels at 160 µm). The 24 µm detector is identical to one of the IRS short wavelength modules. The 70 µm detector uses gallium-doped germanium technology, and the 160 µm detector also uses gallium-doped germanium, but with mechanical stress added to each pixel to lower the bandgap and extend sensitivity to this long wavelength.


To commemorate 1000 days of infrared wonders, the program is released a gallery of the 10 best IRAC images. They are stunning! The warm-mission images particularly highlight the continuing capabilities of Spitzer. NASA's Senior Review Panel has recommended extending the Spitzer warm mission through 2015. They specifically commended the Spitzer team for telescope improvements that have made it a powerful instrument for science, especially in exoplanet studies. 


During its 1000-day undertaking, IRAC used its two shortest-wavelength infrared sensors. However, some of the images include data collected during the cold mission, when all four of its infrared sensors could function. Enjoy!



IRAC not only probes what is known - it also has uncovered some mysterious objects like this so-called "tornado" nebula.


Because the camera is sensitive to light emitted from shocked molecular hydrogen (seen here in green), astronomers think that this strange beast is the result of an outflowing jet of material from a young star that has generated shock waves in surrounding gas and dust.


The famous nebula in Orion, located about 1340 light-years from Earth, is actively making new stars today.


Although the optical nebula is dominated by the light from four massive, hot young stars, IRAC reveals many other young stars still embedded in their dusty womb.


It also finds a long filament of star-forming activity containing thousands of young protostars.


Some of these stars may host still-forming planets.


This image was taken during Spitzer's warm mission.


After a long life of hydrogen-burning nuclear fusion, stars move into later life states whose details depend on their masses.


This IRAC image of the Helix Nebula barely spots the star itself at the center, but clearly shows how the aging star has ejected material into space around it, creating a "planetary nebula".


The Helix Nebula is located 650 light-years away in the constellation Aquarius.


This image was taken during Spitzer's warm mission.


The early universe contained only hydrogen and helium. No other chemical elements existed.


All of the elements needed for life were created later in the nuclear furnaces of stars, and then ejected into space.


IRAC studies how stars mature. It can observe how the processes of stellar evolution affect the environment.


The Trifid Nebula hosts stars at all stages of life, surrounded by gas and dust that form a beautiful roseate nebula.


It's located 5400 light-years away in the constellation Sagittarius.


Within galaxies like the Milky Way, giant clouds of gas and dust coalesce under the influence of gravity until new stars are born.


IRAC can both measure the warm dust and peer deeply into it to study the processes at work.


In this giant cloud several stellar nurseries can be seen, some still within the tips of dusty "mountains of creation".


This image shows the eastern edge of a region known as W5, near the Perseus constellation 7000 light-years away.


After blowing away its natal material, the young star cluster seen here emits winds and harsh ultraviolet light that sculpt the remnant cloud into fantastic shapes.


Astronomers are not sure when that activity suppresses future star formation by disruption, and when it facilitates star formation through compression.


The cluster, known as DR22, is in the constellation Cygnus the Swan.


This image was taken during Spitzer's warm mission.


IRAC has systematically imaged the entire Milky Way disk, assembling a composite photograph containing billions of pixels with infrared emission from everything in this relatively narrow plane.


The image here shows five end-to-end strips spanning the center of our galaxy.


This image covers only one-third of the whole galactic plane.


Collisions play an important role in galaxy evolution.


These two galaxies - the Whirlpool and its companion - are relatively nearby at a distance of just 23 million light-years from Earth.


IRAC sees the main galaxy as very red due to warm dust - a sign of active star formation that probably was triggered by the collision.


Star formation helps shape a galaxy's structure through shock waves, stellar winds, and ultraviolet radiation.


In this image of the nearby Sombrero Galaxy, IRAC clearly sees a dramatic disk of warm dust (red) caused by star formation around the central bulge (blue).


The Sombrero is located 28 million light-years away in the constellation Virgo.


The many points of light in this field aren't stars but entire galaxies.


A few, like the mini-tadpole at upper right, are only hundreds of millions of light-years away so their shapes can be discerned.


The most distant galaxies are too far away and appear as dots. Their light is seen as it was over ten billion years ago, when the universe was young.


Images in higher resolution can be seen here.



Credits: NASA, JPL-Caltech, Harvard-Smithsonian Center for Astrophysics

Filter Blog

By date:
By tag: